In more than 40 episodes spanning 75 years, equity and bond fund investors have defied predictions that they would panic and spark crises. Yet banking regulators won’t let go of their “run” scenario. Why?

After three weeks of repeatedly arguing her Brexit deal was the only one in town, the prime minister finally acknowledged what has been obvious for days — that she has failed to convince enough of her backbenchers of the deal's merits. May pulled Tuesday’s crunch vote of British MPs with the extraordinary admission that her plan would have been “rejected by a significant margin.”

The imminent threat to her premiership that would have followed such a critical defeat has been kept at bay, but as Hilary Benn, chair of the House of Commons Brexit committee, put it, she may merely be “postponing the inevitable.”

Short of a revisiting of the agreement she negotiated with Brussels — something the EU has already ruled out — May’s deal looks likely to be rejected by parliament when she eventually brings it back for a vote, be that in a matter of days or weeks. After that, the threat to her authority will return.

On Tuesday, the prime minister embarked on a whistle-stop tour of Europe in the hope that EU leaders can throw her a lifeline. She began with breakfast in the Hague with Dutch Prime Minister Mark Rutte, followed by lunch in Berlin with Angela Merkel. May then heads to Brussels for meeting with Council President Donald Tusk and Commission President Jean-Claude Juncker.

MPs will return to the Commons on Tuesday for an emergency debate on the delay, forced by Labour leader Jeremy Corbyn.

While she works to secure "assurances" from EU leaders on aspects of the deal, the immediate threat at home appears to have receded for now. The opposition Labour Party said Monday it would withhold a vote of no confidence in the government and wait for May to “bring the same deal back to the House of Commons without significant changes” and then strike.

While it is possible her own backbench MPs will challenge her leadership of the party in the interim, they must still calculate when they are most likely to win an internal party vote on toppling her, because failure to do so would mean she could not be challenged again for a year.

Whether or not May survives parliament's vote when it eventually comes, it seems unlikely she will have swerved the looming political crisis it will bring.

Should the prime minister fail to get a deal through the House of Commons, the chances of an economically disruptive exit with no deal at all, or a general election or second referendum all rise dramatically. The way ahead will depend on whether any of Westminster's Brexit tribes manage to assemble a majority for their preferred route out of the crisis.

MPs will return to the Commons on Tuesday for an emergency debate on the delay, forced by Labour leader Jeremy Corbyn. However the government has been able to enact the deferral of the vote via a loophole in parliamentary procedure. Their approach was described as “deeply discourteous” by Speaker of the House of Commons John Bercow.

But even as the speaker granted the debate to the Labour leader, the house descended into raucous chaos as a backbench Labour MP, Lloyd Russell-Moyle, walked towards the speaker's chair and picked up the 1.5 meter long, silver gilt mace. He proceeded to walk towards the door of the chamber carrying the object but was intercepted by two Commons officials who return the mace to its place between the two front benches.

The ceremonial club is the symbol of royal authority and without it, MPs cannot sit and pass laws.

May's deal is dead, long live May's deal!

Earlier, in her House of Commons statement on Monday afternoon, May admitted defeat to an already restless House of Commons, saying she would go back to the EU to seek “additional reassurance” that the U.K. won’t be stuck permanently in the so-called backstop. That is the arrangement agreed by her government and Brussels in order to avoid a hard border on the island of Ireland.

Yet, in nearly the same breath, the prime minister said she was still “in absolutely no doubt that this deal is the right one,” and emphasized that reopening the Withdrawal Agreement — the legally binding element of the deal agreed with the EU — is fraught with risk.

In other words, the government of the U.K. and the EU have a draft, legally-binding deal, which they are not going to change. But they are now, with barely 108 days until the U.K.'s exit date, going to spend an unknown number of days seeking a way to convince a bloc of adamantly opposed MPs to consider changing their minds.

“The Withdrawal Agreement is non-negotiable and nothing can be done to allow it to be withdrawn from unilaterally” — EU27 diplomat

European Council President Donald Tusk confirmed leaders would rearrange their diaries and hold a meeting on Brexit on Thursday, as part of the scheduled European Council summit. But they will not, he made clear, “renegotiate the deal, including the backstop.” The EU is “ready to discuss how to facilitate U.K. ratification,” he said. In other words, they will help May try and twist the arms of some of her more recalcitrant MPs.

His message was backed up by the Irish prime minister Leo Varadkar, who spoke to Tusk on Monday afternoon and said in a statement that the current agreement is the "best option" and preparations for a 'no deal' outcome should intensify."

Clock ticking

Downing Street set no clear timetable for coming back to MPs with the assurances May is seeking, with officials saying that it will take as long as it takes for the prime minister to be satisfied she has something from the EU that would change MPs’ minds.

May mentioned a date of January 21, which is written into U.K. legislation as a deadline for the government to set out the next steps if it can’t get a deal. Technically, now that there is a deal agreed with Brussels that deadline is void, but the prime minister nevertheless appears to see it as the last moment she can hold a vote on her plan — a requirement enshrined in law.

Downing Street hopes that, with time running out, fear of a no-deal exit or the continuing uncertainty of an election or a fresh referendum, will focus the minds of MPs on all sides of the Brexit debate and change the political context.

A vote in late January would leave little more than two months to implement Brexit. A Downing Street spokesman insisted this would still leave enough time to push through all the legislation required to implement the U.K.’s exit, but added that the closer the U.K. came to its scheduled exit on March 29, 2019, without the deal ratified, “the more decisions need to be made” by government to trigger expensive contingency plans for the no-deal exit British businesses dread.

U.K. firms, desperate for certainty about the weeks and months ahead, reacted with undisguised exasperation Monday. “Firms are looking on with utter dismay at the ongoing saga in Westminster,” said Adam Marshall, director general of the British Chambers of Commerce.

'Warm words'

Precisely what assurances May can win in Brussels is unclear.

May told MPs, in her inimitable style, that she was looking at “new ways of empowering the House of Commons to ensure that any provision for a backstop has democratic legitimacy and to enable the house to place its own obligations on the government to ensure that the backstop cannot be in place indefinitely.”

Confusing as that sounds, it seems to boil down to a promise that the backstop arrangement could not be entered into without MPs’ approval.

European Council President Donald Tusk | Grzegorz Michalowski/EPA

Key opponents of the prime minister weren't buying it.

“If the prime minister comes back with a statement, warm words, it is completely irrelevant because the [Withdrawal Agreement] treaty outranks it,” said Jacob Rees-Mogg, chair of the Euroskeptic European Research Group of backbench Conservatives. “Unless it is an amendment to the treaty, is it pointless.”

Nigel Dodds, Westminster leader of the Democratic Unionist Party, which props up May’s government, asked how the prime minister did not “get it by now” that it's the legally-binding Withdrawal Agreement that he and his Brexiteer Tory allies are against.

Nothing short of re-writing it will do. And that is the one thing the EU can’t give.

Jacob Rees-Mogg, hardline Tory Brexiteer | Dan Kitwood/Getty Images

“The Withdrawal Agreement is non-negotiable and nothing can be done to allow it to be withdrawn from unilaterally,” said an EU27 diplomat. There may be scope to adjust the non-legally binding political declaration that accompanied the agreement, they added. “That’s where the potential action is.”

But for now, it looks highly unlikely that any diplomatic action over the coming days or weeks will change the fundamentals of May’s position.

She does still have the option of disappointing her Euroskeptic MPs and the DUP, and seeking the support of opposition parties for a softer form of Brexit or even a second referendum. But that carries the risk of the DUP instantly pulling the plug on the confidence and supply agreement that props up her government, or of Brexiteer Conservatives finally massing the numbers to challenge her leadership of the party.